ABSTRACT
OBJECTIVE: To analyze the changes in the body composition of morbidly obese patients induced by a very low-calorie diet. METHODS: We evaluated 120 patients selected from a university hospital. Body composition was assessed before and after the diet provided during hospitalization, and changes in weight, body mass index, and neck, waist and hip circumferences were analyzed. Bioimpedance was used to obtain body fat and fat-free mass values. The data were categorized by gender, age, body mass index and diabetes diagnosis. RESULTS: The patients consumed the diet for 8 days. They presented a 5% weight loss (without significant difference among groups), which represented an 85% reduction in body fat. All changes in body circumference were statistically significant. There was greater weight loss and a greater reduction of body fat in men, but the elderly showed a significantly higher percentage of weight loss and greater reductions in body fat and fat-free mass. Greater reductions in body fat and fat-free mass were also observed in superobese patients. The changes in the diabetic participants did not differ significantly from those of the non-diabetic participants. CONCLUSIONS: The use of a VLCD before bariatric surgery led to a loss of weight at the expense of body fat over a short period, with no significant differences in the alteration of body composition according to gender, age, body mass index and diabetes status.
Subject(s)
Humans , Male , Female , Middle Aged , Body Composition , Obesity, Morbid/diet therapy , Weight Loss/physiology , Diet, Reducing/methods , Bariatric Surgery , Obesity, Morbid/surgery , Preoperative Care/methods , Body Mass Index , Sex Factors , Prospective Studies , Age Factors , Diabetes Mellitus/diet therapy , Diabetes Mellitus/physiopathology , Waist Circumference , Hip/anatomy & histology , Hospitalization/statistics & numerical data , Neck/anatomy & histologyABSTRACT
ABSTRACT Background: Body mass index (BMI) has some limitations for nutritional diagnosis since it does not represent an accurate measure of body fat and it is unable to identify predominant fat distribution. Aim: To develop a BMI based on the ratio of trunk mass and height. Methods: Fifty-seven patients in preoperative evaluation to bariatric surgery were evaluated. The preoperative anthropometric evaluation assessed weight, height and BMI. The body composition was evaluated by bioimpedance, obtaining the trunk fat free mass and fat mass, and trunk height. Trunk BMI (tBMI) was calculated by the sum of the measurements of the trunk fat free mass (tFFM) and trunk fat mass (tFM) in kg, divided by the trunk height squared (m2)). The calculation of the trunk fat BMI (tfBMI) was calculated by tFM, in kg, divided by the trunk height squared (m2)). For the correction and adjustment of the tBMI and tfBMI, it was calculated the relation between trunk extension and height, multiplying by the obtained indexes. Results: The mean data was: weight 125.3±19.5 kg, height 1.63±0.1 m, BMI was 47±5 kg/m2) and trunk height was 0.52±0,1 m, tFFM was 29.05±4,8 kg, tFM was 27.2±3.7 kg, trunk mass index was 66.6±10.3 kg/m², and trunk fat was 32.3±5.8 kg/m². In 93% of the patients there was an increase in obesity class using the tBMI. In patients with grade III obesity the tBMI reclassified to super obesity in 72% of patients and to super-super obesity in 24% of the patients. Conclusion: The trunk BMI is simple and allows a new reference for the evaluation of the body mass distribution, and therefore a new reclassification of the obesity class, evidencing the severity of obesity in a more objectively way.
RESUMO Racional: O índice de massa corporal (IMC) para diagnóstico nutricional apresenta limitações, pois não representa medida precisa da adiposidade corporal, podendo assim subestimar a presença de obesidade. Objetivo: Desenvolver um índice de massa corporal baseado entre a relação da massa e altura do tronco. Método: Cinquenta e sete pacientes em preparo pré-operatório para cirurgia bariátrica foram submetidos à avaliação antropométrica (peso, altura e índice de massa corporal). Para cálculo do IMC do tronco foi avaliada a composição corporal pela bioimpedância, obtendo-se a massa livre de gordura e massa de gordura do tronco; a medida do tronco foi calculada pela diferença entre a altura a partir da sétima vértebra cervical e a extensão dos membros inferiores. O cálculo do IMC do tronco (IMCt) foi a soma das medidas da massa livre de gordura do tronco (MLGt) e massa de gordura do tronco (MGt), em kg, dividindo-se pelo quadrado da altura do tronco (m2)). O IMC de gordura do tronco (IMCgt) foi calculado utilizando a MGt, em kg, dividindo-a pelo quadrado da altura do tronco (m2)). Para correção e ajuste do IMCt e IMCgt foi calculada a relação entre os valores de extensão do tronco e da altura, multiplicando-se pelo valor dos índices obtidos. Resultados: As médias do peso e altura foram de 125,3±19,5 kg e 1,63 m±0,1, respectivamente, e do IMC de 47±5 kg/m2). A média da altura do tronco foi de 0,52±0,1 m, da MLGt de 29,05±4,8 kg, da MGt de 27,2±3,7 kg, do IMCt de 66,6±10,3 kg/m², e do IMCgt 32,3±5,8 kg/m². Em 93% dos pacientes houve aumento da classificação da gravidade da obesidade com o cálculo do IMCt . Nos pacientes com obesidade grau III, o IMCt alterou a classificação para super-obesidade em 72% dos pacientes e para super-super obesidade em 24% dos pacientes. Conclusão: O IMC do tronco é método antropométrico acessível e prático, que permite a reclassificação do IMC baseado na distribuição da massa do tronco, evidenciando de forma mais clara a gravidade da obesidade.
Subject(s)
Humans , Male , Female , Adolescent , Adult , Middle Aged , Young Adult , Body Mass Index , Thorax , Body Composition , Body Height , Obesity/classificationABSTRACT
OBJECTIVE: The aim of our study was to evaluate associations between maximum voluntary contraction torques of the lower limbs and body composition for subjects with severe obesity. METHODS: Body composition was evaluated by bioelectrical impedance analysis, and maximum voluntary contraction torques of the lower limbs were measured using an isokinetic dynamometer. One hundred thirty-two patients were enrolled (100 females and 32 males). Eighty-seven patients had a body mass index between 40 and 49.9 kg/m2 (the A group), and 45 patients had a body mass index between 50 and 59.9 kg/m2 (the B group). RESULTS: Absolute extension and flexion torques had weak associations with fat-free mass but a moderate association with absolute extension torque and fat-free mass of the lower limbs. There were no significant differences between the A and B groups with respect to absolute extension and flexion torques. For the A group, absolute extension and flexion torques were moderately associated with fat-free mass and with fat-free mass of the lower limbs. For the B group, there were only moderate associations between absolute extension and flexion torques with fat-free mass of the lower limbs. CONCLUSIONS: Our findings demonstrate that both groups exhibited similar absolute torque values. There were weak to moderate associations between absolute extension and flexion torques and fat-free mass but a moderate association with fat-free mass of the lower limbs. Individuals with severe obesity should strive for greater absolute torques, fat-free mass and especially fat-free mass of the lower limbs to prevent functional limitations and physical incapacity.